What is it to be mentally healthy? In the ongoing movement to promote mental health, to reduce stigma and to establish parity between mental and physical health, there is a clear enthusiasm about this concept and a recognition of its value in human life. However, it is often unclear what mental health means in all these efforts and whether there is a single concept underlying them. Sometimes the initiatives for the sake of mental health are aimed just at reducing mental illness, thus implicitly identifying mental health with the absence of diagnosable psychiatric disease. More ambitiously, there are high-profile proposals to adopt a positive definition, identifying mental health with psychic or even overall wellbeing. We argue against both: a definition of mental health as mere absence of mental illness is too thin, too undemanding, and too closely linked to psychiatric value judgments, while the definition in terms of wellbeing is too demanding and potentially oppressive. As a compromise we sketch out a middle position. On this view mental health is a primary good, that is the psychological preconditions of pursuing any conception of the good life, including wellbeing, without being identical to wellbeing.

Albert Einstein (1879–1955) is well known as the most prominent physicist of the twentieth century. His contributions to twentieth-century philosophy of science, though of comparable importance, are less well known. Einstein’s own philosophy of science is an original synthesis of elements drawn from sources as diverse as neo-Kantianism, conventionalism, and logical empiricism, its distinctive feature being its novel blending of realism with a holist, underdeterminationist form of conventionalism. Of special note is the manner in which Einstein’s philosophical thinking was driven by and contributed to the solution of problems first encountered in his work in physics.

Joane Petrizi (12^th century)—the most significant Georgian medieval philosopher—devoted intensive work to neo-Platonic philosophy. He translated Nemesius of Emesa’s On the Nature of Man into Georgian, a work which in that day attracted considerable attention. Of particular importance is his Georgian translation of Proclus’s Elementatio theologica, to which he also wrote a step-by-step commentary. Petrizi’s commentary on the Elementatio theologica represents a significant effort at reception inasmuch as the Georgian philosopher interprets the work immanently, that is, on the basis of Proclus’s philosophy itself.

In a recent issue of Bioethics, I argue that compulsory moral bioenhancement should be administered covertly. Alexander Zambrano has criticized this argument on two fronts. First, contrary to my claim, Zambrano claims that the prevention of ultimate harm by covert moral bioenhancement fails to meet conditions for permissible liberty-restricting public health interventions. Second, contrary to my claim, Zambrano claims that covert moral bioenhancement undermines autonomy to a greater degree than does overt moral bioenhancement. In this paper, I rebut both of these arguments, then finish by noting important avenues of research that Zambrano’s arguments motivate.

It is widely thought that there is an important argument to be made that starts with premises taken from the science of physics and ends with the conclusion of physicalism. Maybe the argument isn’t decisive, and maybe physics isn’t univocal on the topic. Still, surely there is some sort of physics­based argument for physicalism to be made. My question in what follows is, just how should this argument go?

Nicolaus Copernicus (1473–1543) was a mathematician and astronomer who proposed that the sun was stationary in the center of the universe and the earth revolved around it. Disturbed by the failure of Ptolemy’s geocentric model of the universe to follow Aristotle’s requirement for the uniform circular motion of all celestial bodies and determined to eliminate Ptolemy’s equant, an imaginary point around which the bodies seemed to follow that requirement, Copernicus decided that he could achieve his goal only through a heliocentric model. He thereby created a concept of a universe in which the distances of the planets from the sun bore a direct relationship to the size of their orbits.

Historians recently rehabilitated Einstein’s “physical strategy” for General Relativity (GR). Independently, particle physicists similarly re-derived Einstein’s equations for a massless spin 2 field. But why not a light massive spin 2, like Neumann and Seeliger did to Newton? Massive gravities are bimetric, supporting conventionalism over geometric empiricism. Nonuniqueness lets field equations explain geometry but not vice versa. Massive gravity would have blocked Schlick’s critique of Kant’s synthetic a priori. Finally in 1970 massive spin 2 gravity seemed unstable or empirically falsified. GR was vindicated, but later and on better grounds. However, recently dark energy and theoretical progress have made massive spin 2 gravity potentially viable again.

This survey covers some of the main philosophical debates raised by the framework of effective field theories during the last decades. It is centered on three issues: whether effective field theories underpin a specific realist picture of the world, whether they support an anti-reductionist picture of physics, and whether they provide reasons to give up the ultimate aspiration of formulating a final and complete physical theory. Reviewing the past and current literature, we argue that effective field theories do not give convincing reasons to adopt a particular stance towards these speculative issues. They hold good prospects for asking ontologically perspicuous and sensible questions about currently accessible domains. With respect to more fundamental questions, however, the only certainty is provisional and instrumental: effective theories are currently indispensable for conducting fruitful scientific research.

In a series of papers Colbeck and Renner (2011, 2015a,b) claim to have shown that the quantum state provides a complete description for the prediction of future measurement outcomes. In this paper I argue that thus far no solid satisfactory proof has been presented to support this claim. Building on the earlier work of Leifer (2014), Landsman (2015) and Leegwater (2016), I present and prove two results that only partially support this claim. I then discuss the arguments by Colbeck, Renner and Leegwater concerning how these results are to generalize to the full claim. This argument turns out to hinge on the implicit use of an assumption concerning the way unitary evolution is to be represented in any possible completion of quantum mechanics. I argue that this assumption is unsatisfactory and that possible attempts to validate it based on measurement theory also do not succeed.

In her book Kant on Reflection and Virtue, Melissa Merritt presents an extended defense of Kant’s “reflective ideal” against the objection that it is “precious, hyper-deliberate and repugnantly moralistic” (2). This defense is in part constituted by the articulation of a theory of cognitive virtue, which Merritt attributes to Kant. Merritt hopes that Kant’s statement that we have a “duty to reflect” (e.g. A261/B317) may be mitigated within the context of such a virtue theory. The requirement to reflect is not, as the “caricature” has it, that one must constantly step back and deliberate as to whether something is worth doing or accepting as true. Rather, “the requirement is to be met by putting one’s cognitive capacities to use in the right way, or in the right spirit: reflection can be adverbial, and it is not essentially episodic…what drives the development of cognitive and moral character is an essentially outward-directed interest in knowing” (206), which Merritt identifies with Kant’s conception of a “healthy human understanding.” This interpretation, she argues, allows the Kantian reflective ideal to avoid being overly demanding, and it helps explain how some kinds of cognitive activity that are not deliberate (at least as that term is typically understood) might nevertheless be justified or “cognitively excellent” (205).

In our representations of the world, especially in physics, (mathematical) infinities play a crucial role. The continuum of the real numbers, \(\Re\), as a representation of time or of one-dimensional space is surely the best known example and, by extension, the \(n\)-fold cartesian product, \(\Re^{n}\), for \(n\)-dimensional space. However, these same infinities also cause problems. One just has to think about Zeno’s paradoxes or the present-day continuation of that discussion, namely the discussion about supertasks, to see the difficulties (see the entry on supertasks in this encyclopedia for a full treatment).

This is a work in analytic metaphysics, which addresses a cluster of interrelated issues at the interface of mereology and persistence over time. In particular, it outlines a defence of a version of Endurance Theory according to which every enduring object is either a mereo-logical simple or a mere sum of mereological simples. It includes, among other things, a proposal of a new way of framing the debate between Endurance Theory and Four-Dimensionalism, a defence of Endurance Theory over Four-Dimensionalism, arguments against the existence of compound substances, and a defence of a traditional metaphysical atom-ism according to which all objects are ultimately made up of microscopic simples.

As is well known, Kant holds that the applicability of the moral ‘ought’ depends on a kind of agent-causal freedom that is incompatible with the deterministic structure of phenomenal nature. I argue that Kant understands this determinism to threaten not just morality but the very possibility of our status as rational beings. Rational beings exemplify “cognitive control” in all of their actions, including not just rational willing and the formation of doxastic attitudes, but also more basic cognitive acts such as judging, conceptualizing, and synthesizing.

The “Cosmological Constant Problem” (CCP) has historically been understood as describing a conflict between cosmological observations in the framework of general relativity (GR) and theoretical predictions from quantum field theory (QFT), which a future theory of quantum gravity ought to resolve. I argue that this view of the CCP is best understood in terms of a bet about future physics made on the basis of particular interpretational choices in GR and QFT respectively. Crucially, each of these choices must be taken as itself grounded in the success of the respective theory for this bet to be justified.

It is widely recognized that the process used to make observations often has a significant effect on how hypotheses should be evaluated in light of those observations. Arthur Stanley Eddington (1939, Ch. II) provides a classic example. You’re at a lake and are interested in the size of the fish it contains. You know, from testimony, that at least some of the fish in the lake are big (i.e., at least 10 inches long), but beyond that you’re in the dark. You devise a plan of attack: get a net and use it to draw a sample of fish from the lake. You carry out your plan and observe: O : 100% of the fish in the net are big.

Certain metaphysical views are thought to have implications for the kinds of feelings that are appropriate to have. For instance, many philosophers maintain that we lack free will and that, as a result, reactive attitudes like resentment are inappropriate. Resentment would only be appropriate if people had genuine libertarian free will; since people lack such free will, we should not resent people even when they do us wrong (e.g., Pereboom 2001, Sommers 2007). Buddhist metaphysics also has implications for the kinds of reactive attitudes that are appropriate to have. Insofar as Buddhism denies the existence of a self, emotions that depend on a representation of self are based on a fundamental mistake.

We approach the problem of the extended mind from a radically non-dualist perspective. The separation between mind and matter is an artefact of the outdated mechanistic worldview, which leaves no room for mental phenomena such as agency, intentionality, or experience. We propose to replace it by an action ontology, which conceives mind and matter as aspects of the same network of processes. By adopting the intentional stance, we interpret the catalysts of elementary reactions as agents exhibiting desires, intentions, and sensations. Autopoietic networks of reactions constitute more complex super-agents, which moreover exhibit memory, deliberation and sense-making. In the specific case of social networks, individual agents coordinate their actions via the propagation of challenges. The distributed cognition that emerges from this interaction cannot be situated in any individual brain. This non-dualist, holistic view extends and operationalizes process metaphysics and Eastern philosophies. It is supported by both mindfulness experiences and mathematical models of action, self-organization, and cognition.

Wang Yangming (1472–1529) was a Chinese statesman, general, and Neo–Confucian philosopher. He was one of the leading critics of the orthodox Neo–Confucianism of Zhu Xi (1130–1200). Wang is perhaps best known for his doctrine of the “unity of knowing and acting,” which can be interpreted as a denial of the possibility of weakness of will.

Mencius (fourth century BCE) was a Confucian philosopher. Often referred to as the “Second Sage” of Confucianism (meaning second in importance only to Confucius himself), Mencius is best known for his claim that “human nature is good.” He has attracted interest in recent Western philosophy because his views on the virtues, ethical cultivation, and human nature have intriguing similarities with but also provocative differences from familiar Humean and Aristotelian formulations.

A venerable view holds that a border between perception and cognition is built into our cognitive architecture, and that this imposes limits on the way information can flow between them. While the deliverances of perception are freely available for use in reasoning and inference, there are strict constraints on information flow in the opposite direction. Despite its plausibility, this approach to the perception-cognition border has faced criticism in recent years. This paper develops an updated version of the architectural approach, which I call the dimension restriction hypothesis (DRH).

According to Jens Høyrup, the propositions 1 to 10 of book 2 of Euclid’s Elements function as a critique of previous non-rigorous procedures of Old Babylonian mathematics. Høyrup’s remarks on his notion of critique are disseminated throughout his works. Here, we take them into account to make an integrated presentation of the notion of critique that also looks to reveal features left implicit in Høyrup’s account.

A relevant issue in the philosophy of science is the demarcation problem: how to distinguish science from nonscience, and, more specifically, science from pseudoscience. Sometimes, the demarcation problem is debated from a very general perspective, proposing demarcation criteria to separate science from pseudoscience, but without discussing any specific field in detail. This article aims to focus the demarcation problem on particular disciplines or theories. After considering a set of demarcation criteria, four pseudosciences are examined: psychoanalysis, speculative evolutio nar y psychology, universal grammar, and string theory. It is concluded that these theoretical frameworks do not meet the requirements to be considered genuinely scientific.

This paper presents a sketch of a moderately anti-realist position in philosophy of science that is a modification of Van Fraassen’s constructive empiricism and that I call ‘adaptive empiricism’. This modification is motivated by the intuition that assessing what is or is not observable should be an important element of theory choice for an empiricist. (I use cases of underdetermination as examples.) Thus I argue that Van Fraassen’s distinction between what is observable and what is unobservable should be adapted to changing theoretical and experimental contexts. I close with some ideas as to how to develop this position more fully.

The mathematical nature of modern physics suggests that mathematics is bound to play some role in explaining physical reality. Yet, there is an ongoing controversy about the prospects of mathematical explanations of physical facts and their nature. A common view has it that mathematics provides a rich and indispensable language for representing physical reality but that, ontologically, physical facts are not mathematical and, accordingly, mathematical facts cannot really explain physical facts. In what follows, I challenge this common view. I argue that, in addition to its representational role, in modern physics mathematics is constitutive of the physical. Granted the mathematical constitution of the physical, I propose an account of explanation in which mathematical frameworks, structures, and facts explain physical facts. In this account, mathematical explanations of physical facts are either species of physical explanations of physical facts in which the mathematical constitution of some physical facts in the explanans are highlighted, or simply explanations in which the mathematical constitution of physical facts are highlighted. In highlighting the mathematical constitution of physical facts, mathematical explanations of physical facts deepen and increase the scope of the understanding of the explained physical facts. I argue that, unlike other accounts of mathematical explanations of physical facts, the proposed account is not subject to the objection that mathematics only represents the physical facts that actually do the explanation. I conclude by briefly considering the implications that the mathematical constitution of the physical has for the question of the unreasonable effectiveness of the use of mathematics in physics.

Must a theory of quantum gravity have some truth to it if it can recover general relativity in some limit of the theory? This paper answers this question in the negative by indicating that general relativity is multiply realizable in quantum gravity. The argument is inspired by spacetime functionalism – multiple realizability being a central tenet of functionalism – and proceeds via three case studies: induced gravity, thermodynamic gravity, and entanglement gravity. In these, general relativity in the form of the Einstein field equations can be recovered from elements that are either manifestly multiply realizable or at least of the generic nature that is suggestive of functions. If general relativity, as argued here, can inherit this multiple realizability, then a theory of quantum gravity can recover general relativity while being completely wrong about the posited microstructure. As a consequence, the recovery of general relativity cannot serve as the ultimate arbiter that decides which theory of quantum gravity that is worthy of pursuit, even though it is of course not irrelevant either qua quantum gravity. Thus, the recovery of general relativity in string theory, for instance, does not guarantee that the stringy account of the world is on the right track; despite sentiments to the contrary among string theorists.

This paper develops a number of quantum mechanical characterisations of Stern-Gerlach. It discusses areas of vagueness in their formulation. Philosophers criticise quantum mechanics for unacceptable vagueness in connection with the measurement problem. The quantum formulation problems identified by this paper go beyond the locus of philosophical criticism. It concludes with an open question, are some areas of vagueness in quantum mechanics more acceptable philosophically than others and, if so, why?